Komatsu 930E-2, Руководство по ремонту

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Disassembly
The parts installed in the valve body for the “B1” and
“B2” bores are identical, however the parts must not
be interchanged between the two bores.
1. Thoroughly clean valve to remove dirt accumula-
tion. Drain all oil from all ports of the valve by
rotating the valve over a suitable container.
2. Use a felt tip pen to mark manifold body (1, Figure
3-11) and valve body (2) to ensure correct reas-
sembly.
NOTE: As the valve is disassembled, lay out parts in
order of disassembly, being certain to note the valve
body bore from which they are removed. Parts must
be reinstalled in the same bore from which they are
removed.
3. Secure valve in an upright position in a vice.
4. Remove capscrews securing the differential pres-
sure switch (3) to the valve body. Remove and
discard seals behind differential pressure switch
ports. Refer to “Differential Pressure Switch” for
disassembly.
5. Remove the two socket head capscrews (20)
retaining the manifold body (1) to the valve body
(2). Remove manifold body and discard O-rings
(18).
6. Remove plungers (16) and sleeves (17).
7. Remove controller from vice.
8. Remove the four capscrews and washers (7) from
the base of the valve.
9. Remove the sleeve retainer (6).
10. With the valve upright, the plug (5) should fall out.
If not, tap lightly to dislodge.
11. Remove the spools (12), reaction plungers (8) and
spool return springs (11). Keep parts separate so
they may be installed in the same spool from
which they were removed.
12. Remove and discard the packing (4) from the
counterbore in the base of the valve body.
13. Turn the valve on its side on the work bench and
remove the sleeves (9) from the valve body.
14. Remove seal (10), O-rings (22 & 24), and backup
rings (21 & 23) and discard.
15. Remove spring seats (13 & 15) and regulator
springs (14).
Cleaning and Inspection
1. Clean all metal parts with solvent and air dry.
2. Apply a light film of type C-4 hydraulic oil to
plungers (14, Figure 3-11) and insert in sleeves
(15). Sleeves must slide smoothly and freely in
sleeve bores. If parts do not slide smoothly or
excessive wear is apparent, replace both the
sleeve and plunger.
3. Apply a light film of oil to regulator spools (12) and
slide into bore of sleeves (9). Spools must slide
smoothly and freely in sleeve bores. If parts do
not slide smoothly or excessive wear is apparent,
replace both the sleeve and spool.
4. Inspect each spring carefully for cracks or breaks.
Any spring with a crack or break must be re-
placed. If the valve was not reaching proper regu-
lated pressure, replace the regulator springs.
5. Lubricate all parts with a thin coat of clean type
C-4 hydraulic oil. Take care to keep components
protected from contamination.
Assembly
1. Install sleeves (17, Figure 3-11) in bores in top of
valve body (2).
2. Install plungers (16) in sleeves as shown in Figure
3-11.
3. Apply film of oil to O-rings (18) and position in
grooves on top of valve body.
4. Position manifold body (1) on valve body, aligning
marks made during disassembly.
5. Secure manifold to valve body with two socket
head capscrews (20). Only finger tighten cap-
screws.
6. Preassemble upper spring seat (15), spring (14)
and lower spring seat (13). Insert assembly into
bore from bottom of valve. Be certain upper spring
seat is positioned against plunger (16). Repeat
for other bore.
7. Install sleeve packing seal (10). Refer to Detail “A”
and “B”, Figure 3-11 and install O-rings (22 & 24)
and backup rings (21 & 23) in the sleeve (9)
grooves.
8. Apply a light film of oil to sleeve seals. Carefully
push sleeves (9) into their respective bores in the
valve body until flange at base of sleeves contact
valve body.
9. Preassemble regulator spool (12) as follows:
a. Insert spool springs (11) into spool bore.
b. Insert reaction plungers (8) into spool bores
and springs.
J03019 1/99 Brake Circuit Component Service J3-17